5 celeb diets that don't work

Gwyneth Paltrow has been known to endorse a gluten-free diet. (REUTERS/Mario Anzuoni)

Banking on a trendy weight-loss plan to help you shed pounds? Before you give up gluten or get biotyped, check out this list of the top five celebrity-endorsed diets to avoid. Put together by the British Dietetic Association, these regimens are unhealthy and potentially dangerous (and sometimes downright laughable …conquering cravings with air?!). The Breatharian Diet It's not exactly a surprise that this diet—which involves pretending you don't need food or water and can survive on air and sunlight alone—is the biggest fraud of them all. Earlier this year, Michelle Pfeiffer told an interviewer that she was briefly involved in a cult that followed this plan—and it's similar to Madonna's supposed regimen of gulping air rather than food to feel full. But—shocker—air is not sustenance, and it can't give you the nutrients you need to stay healthy and energized.

Biotyping The BMA also tears down this diet, which Boy George credited with his recent weight loss. It's all about spot-reducing fat by eating certain foods based on your specific hormone type. Sounds great—but unfortunately it's 100 percent bogus. It's impossible to target your weight loss to a specific body part.

The Gluten-Free Diet If you really are allergic to gluten, foods without the protein are a godsend. But they often have the same calorie counts as their gluten-containing counterparts, so deleting gluten won't shrink your hips—no matter what Gwyneth Paltrow says. Want proof? Check out these gluten-free foods that make you gain weight.

Drunkorexia Lady Gaga has said that she follows "the drunk diet." As she revealed in a 2011 interview: "I like to drink whiskey and stuff while I am working. But the deal is I've got to work out every day, and I work out hung over if I am hung over."

Sometimes, drunkorexics will also eat very little throughout the day so they can "spend" the majority of their calories on alcohol. Here's the thing: Not only does drinking your calories deprive you of nutrients your body needs (alcohol is full of empty cals), but boozefests just leave you hungry for a calorie-laden late-night snack and a greasy brunch the next day.

The Dukan Diet Jennifer Lopez is supposedly a fan, and Kate Middleton was said to have followed this diet in the months leading up to her royal wedding. It's a high-protein, no-carb, super-complicated plan that promises to help you melt pounds very quickly…but the book written about the diet also warns that it saps your energy, makes you constipated, and gives you bad breath (how nice!).

Also important to keep in mind: Cutting out entire food groups and keeping such close track of every morsel you eat usually backfires—and often leads to gaining back all the pounds you lost the second you go off the diet.